Research On Key Technologies Of High-Performance And Low-Cost On-Chip Temperature Sensing And Compensation

Intelligent devices in the Industrial Internet can rely on big data to optimize the manage-ment process and improve the level of manufacturing.With the development of integrated circuits,more and more modules are integrated into the same system-on-chip,improving the portability and intelligence of the device.Among them,on-chip temperature sensing and com-pensation,as an indispensable part of the on-chip system,can not only realize the monitoring and regulation of temperature,but also reduce the sensitivity of the module performance to temperature through temperature compensation,and improve system performance.Different application scenarios also present corresponding challenges for on-chip temperature sensing and compensation design,and it is of great significance to study the key technologies of high-performance and low-cost on-chip temperature sensing and compensation for the performance improvement and wide application of on-chip systems.In order to realize the needs of monitoring and temperature compensation using tempera-ture readout value in the system,this paper takes the realization of on-chip temperature sensing as the starting point,studies the on-chip sensor device and analog to digital readout,at the same time expands to the design of temperature compensation directly realized in analog circuits,and explores the key technologies of high-performance and low-cost on-chip temperature sensing and compensation.The main work and innovations are as follows:1.Aiming at the lack of balance of accuracy,power consumption,area and temperature measurement range of the existing temperature sensor scheme based on duty-cycle-modulated output,a temperature sensor design based on duty-cycle-modulated output with balanced per-formance is proposed.By using dynamic element matching with Kelvin connection,the tem-perature sensing error caused by the switch resistance is reduced;with chopping and circuit optimization,the temperature sensing accuracy is further improved and the design power con-sumption is reduced;a continuous-time dynamic single-threshold hysteresis comparator is pro-posed to reduce the power consumption of the voltage to duty-cycle conversion and improves the robustness of the design.Inplemented and verified in a standard 0.13-μm CMOS process,the sensor achieves an inaccuracy of±0.54℃(3σ)from-40℃ to 125℃ and has an active area of 0.086 mm~2.It also achieves a resolution of 60 m K with a conversion time of 1.3 ms,while consuming 39.7μW.2.For the temperature sensing scenario that requires temperature monitoring at higher temperatures(>125℃),a high precision temperature sensor design with higher signal sensi-tivity,lower power consumption,and faster conversion time is explored.This paper proposes a high-precision low-power temperature sensor architecture based on series BJT and compatible with voltage calibration,which can achieve high-precision in a short conversion time.Optimiz-ing the bias circuit,cooperating with the system chopping,correlated double sampling and other technologies have further improved the temperature sensing accuracy and sensing energy effi-ciency.Inplemented and verified in a standard 0.11-μm CMOS process,the sensor achieves an inaccuracy of-0.51℃/0.41℃(3σ)from-40℃ to 125℃ after one-point trim.It also achieves a resolution of 11 m K with a conversion time of 8.2 ms,indicating a good energy efficiency with a resolution Fo M of 109.2 p J·K~2.3.For a sensing system working from-40℃ to 125℃,this paper proposes a relaxation oscillator design with temperature and process variation stability.Through the single-branch-charging-based relaxation oscillator architecture with voltage average feedback,combined with a relatively simple temperature compensation and process variation trimming scheme,the tem-perature stability and consistency of the output frequency are improved.The design is simulated and taped out in a standard 0.11-μm CMOS process.The simulation results show that the typical oscillation frequency of the design is 13.4 MHz.It achieves a frequency temperature coefficient of 28.3 ppm/℃ from-40℃ to 125℃ and a 0.074%/0.1V frequency variation.The measured results verify its phase noise performance.